Cecil, I never did start a thread on my RAS system but it is set up similar to how Bruce was doing his out at the Conderossa. A few years ago my wife picked up a two used fiberglass aquaculture tanks from a UNL auction a for $65 a piece, one 300 gallon and one 75 gallon tank. Both tanks have center drains and slightly concaved bottoms. Here is how I first set it up the bigger 300 gallon tank for my SMB pellet training project.



Filling the tank and adding water.


I did take the surface agitator out and now have two aquarium powerheads pulling water from the bottom of the tank creating a slow circular current in the tank. The SMB seem to like it better and it's easier for me to watch them eat. Each powder head is moving 170 GPH. The fish waste and uneaten food settle in a small area in the bottom of the tank near the drain that I siphon out twice a day after I'm done feeding the SMB, then I add fresh water and let tank slowly overflow through the drain for hour or more every evening. I am collecting the waste water in a 5 gallon bucket and watering my apple trees with it.

Here is an interesting Easter morning picture with sunlight coming in through the door. Both powerheads are running.


I am still fine tunning my RAS systems, as a newbie to this hopefully I am doing it right. grin So far the only fish that have died in it are the RES that I picked up yesterday, two more this morning that just got burried in the apple tree mulch.